Facsimile scanner drum



Aug. 1944- J. v. HOGAN 2,356,999

FACSIMILE SCANNER DRUM Filed Sept. 29, 1941 lNVENT OR Joy/v V L /7 o6/9/V EORNEY Patented Aug. 29, 1944' FACSIMILE SCANNER. DRUM John V. L.Hogan, Forest Hills, N. Y., assignor to Faximile, Inc., New York, N. Y.,a corporation of New York Application September 29, 1941, Serial No.412,709

Claims.

The present invention concerns facsimile scanning devices and inparticular a method of and means for holding copy to be scanned on thescanning drum.

Oneobject of the present invention is to provide an improved andsimplified method of and means for mounting copy to be scanned on thescanning drum of a facsimile reproducer.

Another object is to provide a facsimile copy holder which permitsquickly changing the copy.

Still another object is to provide a facsimile copy holder which willtake copy without cutting in an accurate size and which holds the copyin accurate alignment on the scanning drum.

A further object is to provide means for holding copy on the drum whichalso acts as a light filter to correct contrast effects.

These and other objects will be apparent from the detailed descriptionof the invention given in connection with the various figures of thedrawing.

In the drawing:

Fig. 1 shows a perspective view of one form of the present invention.

Fig. 2 shows an end view of the invention as shown in Fig. 1 and therelation with other parts of a facsimile, pick-up device.

In order to generate a facsimile signal a copy of the material to betransmitted -is scanned with a beam of light. A convenient scanningdevice consists in a drum over which the copy to be transmitted isdrawn; means for rotating the drum at a constant speed to provide onedimension of the scanning operation; and means for moving a lamp andpickup photo-electric cell along the drum to provide the other dimensionof the scanning operation. In order to pick up fine detail in the copythe scanning light must be focused to a time point and the copy must lieflat against an accurately made drum.

A number of methods have been employed in the past to hold the copy flatagainst the scanning drum. These methods havev various disadvantages,such as requiring accurate cutting of the copy to a predetermined size,complicated fixtures, and difficult manipulation. The present inventionconcerns a simple and effective copy mounting device. The scanning drummay be provided with a slot A transparent cover permanently fastened orclipped to the drumalong one edge covers the copy and is secured bymeans of a strip which fits into the slot. The copy may be quicklychanged by pulling the strip from the slot. The transparent cover keepsthe copy flat against the drum even if it is of an odd size or shape.The cover may be color dyed to act as a light filter covering the copy.For instance, a yellow cover has been used to render blue copy morecontrasty, and green to render red parts of the copy darker.

Fig. 1 in which is illustrated oneform of the present invention, shows aperspective view of a scanning drum i adapted to turn on shaft 2. Thetransparent cover 3 is provided with a securing strip 4 along one sideand is permanently fastened to drum I along ridge 6 on the surface ofthe drum. Slot 5 cut at an angle into the surface of drum l is adaptedto receive and hold securing strip 4. The surfaces of slot 5 and/or thesurfaces of securing strip 4 may be roughened to provide a tight grip.The copy to be scanned is slipped under cover I which is then wrappedaround the drum and secured by pushing strip 4 into slot 5. This pullsthe copy tightly against the surface of the drum over its entire area.

Cover 3 may be made of any flexible transparent material. Plastics ofthe order of 0.005 to 0.01 inch thick have been found to be particularlysuited to the use. Suitable materials made under the trade namesVinelite and Fibreloid" have been used. The contrast of the copy as seenby the scanning system, particularly in the case of colored pictures,may be controlled by coloring cover 3 a suitable color.

Fig. 2 shows an end view of drum I, with copy I covered with covers.Various other parts of a facsimile pick-up scanner are also shown. Drumi is rotated by means of motor li operating thru worm 9, worm gear 8,and bearing i0, The copy is scanned with light from lamp i2 brought to asharp focus on copy I by means of lens I3. The modulated light from copyI. is picked up by lens II and brought to bear on photo-electric cellIS. The resulting modulated current from photoelectric cell i5 isamplified in amplifier I 6 and passed to utilization means over wires l1and Hi. This view shows clearly how copy 1 is held against the surfaceof drum i by cover 3. It a1- so shows ridge 6 to which one edge of cover3 is attached and how securing strip 4 fits in slot 5 to hold cover 3 inplace.

Surface reflections from the transparent cover may be avoided bydirecting the light perpendicular to the copy and picking up thereflected light at forty-five degrees to the surface or vice versa.

While only a single embodiment of the present invention has been shownand described, many modifications will be apparent to those skilled inthe art within the spirit and scope of the appended claims.

What is claimed is:

1. A sheet mounting device for holding copy in a facsimile scannerconsisting of a drum, a sheet of transparent material fastened to saiddrum along one edge, and means comprising a wedgeshaped strip fastenedto the other edge of said sheet to be inserted in a longitudinal slot inthe surface of said drum for frictionally holding the other edge forclosely Wrapping said transparent sheet around said drum to hold a sheetof copy against the surface of said drum.

2. A sheet mounting device for holding copy in a facsimile scannerincluding, in combination, a drum, a sheet of transparent material,means for securing one edge of said transparent sheet permanently tosaid drum, and removable friction held means for holding the oppositeedge of said transparent sheet along said drum to hold a sheet of copyagainst the surface of said drum.

3. A sheet mounting device for holding copy in a facsimile scannerincluding in combination, a

aasaeeo slotted drum, a sheet of transparent material, means forpermanently securing one edge of said transparent sheet to said drum,and friction means for holding the opposite edge of said transparentsheet in said slot to hold a sheet of copy against the surface of saiddrum.

4. A sheet mounting device for holding copy in a facsimile scannerincluding in combination, a drum, a sheet of colored tfansparentmaterial, means for securing one edge of said transparent sheet alongthe length of said drum, and means for holding the opposite edge of saidcolored sheet in said slot to hold a sheet of copy against the surfaceof said drum.

5. A sheet mounting device for holding copy in a facsimile scannerincluding in combination, a drum, a sheet of colored light filteringmaterial, means for securing one edge of said colored sheet along thelength of said drum, and means for holding the opposite edge of saidcolored sheet along said drum to hold a sheet of copy against thesurface of said drum.

JOHN V. L. HOGAN.

